Plastic doorknob construction



Oct. 1, 1940. M FALK PLASTIC DOORKNOB CONSTRUCTION Filed Oct. 27. 1938NVENTOR MORE/3 FfiL/. 8%

4 ATTORNEY al mmmmmmmmmmmmmmmwmmmm Patented Oct. 1, 1940 UNITED STATESrrnsrro nooaKNoB CONSTRUCTION Morris Falk, Leominster, Mass, assignor toIndependent Lock Company, Fitchburg, Mass, a corporation ofMassachusetts Application October 27, 1938, Serial No. 237,179

18 Claims.

This invention relates to doorknobs, and more particularly to doorknobsof ornamental character.

The general object of my invention is the provision in a doorknob of asimple and inexpensive construction, but one that is at the same timerugged and is susceptible of highly artistic ornamental embodiment.

Modern taste in builders hardware, and particularly in hardware for thehome which frequently requires adherence to a definite color scheme,calls for great variety in color and finish and multicolored finishesare in great demand. Accordingly dealers and manufacturers of suchhardware must be prepared to supply any given item in a great manycolors and finishes.

Where the article is of one color or finish throughout the problem ofmanufacturing and stocking it in a number of colors and finishes isserious enough, as it prevents production in large runs, therebyincreasing the cost, and the investment involved in stocking the articlein various finishes is enormously increased.

The problem is further complicated where the article is multicolored, asis frequently the case in hardware of modern design in which metallicfittings are frequently used in combination with parts of othermaterials, such as the colorful products of the manufacturers ofsynthetic resins. The consumer may call for a particular color in onepart and another color in another part, and the variety of combinationsthat may be called for is very great.

Among the-objects of my invention is therefore further the provision ofa doorknob whereby it is constituted of interfitting parts that may beseparately finished and enable the inexpensive production ofmulti-colored finishes, the parts of which are interchangeable withother parts, and the parts of which are readily assembled anddisassembled.

As a consequence a dealer need only stock the various parts in a varietyof finishes and colors, and from this stock he may quickly assembly thedesired combination called for. As an alternative, of course, he maystock a limited number of assemblies and additional parts by the use ofwhich one of the assemblies may be converted pointed out, I makereference to the accompany- 7 ing drawing forming a part hereof, inwhich:

Figure 1 is a front elevational view of my improved doorknob;

Figure 2 is an enlarged sectional view thereof; r Figure 3 is anexploded view showing the parts constituting my improved doorknobarranged substantially in the order in which they are assembled, andeach part being shown in perspective;

Figure 4 is a plan view on an enlarged scale of the doorknob bodyportion; 1 1 Figure 5 is a bottom plan View of the interlocking memberof the doorknob;

Referring to the drawing in detail, there is therein designateda'bodyiportion Ill of a. doorknob, a shank portion l2, a washer l i,adapted to be positioned intermediate the body portion and the shank,and a member l8 for interlocking the body portion Ill and the shankportion l2. My improved doorknob further includes a top piece or cap I8adapted -to seat on the body portion Ill and to close the openingtherein. and means to hold the member It in its interlocking position,such means being shown byway of eX-. ample, as a screw 20 and a lockwasher 22.

The body portion In, the shank l2 and the washer H! are so contoured anddimensioned in relation to the locking member 16 that when the latter isdrawn toward the shank, the body portion will be pressed against thewasher M, and all the parts will be firmly interlocked into a rigidunit.

The body portion I0 is shown as of a character that adapts itselfreadily for manufacture from a variety of materials, and in particularfrom one of the many modern synthetic plastics such as phenolformaldehyde condensation products, polymerized vinyl compounds andplasticized cellulosic compounds such as cellulose acetate, all of whichmay be made by a molding, die casting or injection casting method. Thesematerials besides being suitable from the standpoint of ease ofmanufacture, fill the require- 253 which serves to support the flange 19of the top piece or cap I8.

The bottom 28 of the body portion has a centrally, positioned opening 30therein, which opening is non-circular, so that when the projectingportion 32 of the locking member IS, the contour of which iscomplementary to that of the opening 30, is inserted therein, theseparts will be interlocked against relative turning. For this purpose,the portion 32 is shown as in the shape of a cylinder, flattened onopposed sides, as at 33 and is further provided with means for taking upplay between these parts, as will appear hereinafter.

As clearly appears from Figs. 2 and 4, the member I6 is provided with apair of recesses 34 formed in its projecting portion 32, these recessesbeing of a shape to receive therewithin the spaced upstanding lugportions 36 of the shank I2. Between the recesses 34 of the member I6 isa second projecting portion or boss 38 adapted to fit into the spacebetween the lugs or portions 36 of the shank. As can be seen from Fig.2, the flange portions 38 of the member l6 overlie the bottom 28 of thebody portion I8, and all of the parts just described are so contouredthat they will interfit so that relative rotation between them isprevented. They are further so proportioned that the screw 20 will drawthem together in an axial direction until theyare firmly interlocked.

When the lugs 36 are interfitted with the member 16, it will be observedthat the external configuration of the combined portions 3'5 and 33 iscylindrical and of such size that it will be accommodated within theopening 48 of the washer M, the rim portions of which are adapted toseat within the recess 58 of the body portion. In order to allow forvariations between the sizes of the opening 38 and the projection 32 andstill secure firm interfitting, teeth M may be provided at the baseportions of the fiat walls 33 of the projection 32. These teeth may beso contoured and the materials of parts It and [8 so selected that theteeth will bite into the softer materials of the adjacent walls of thebody portion IE) and thereby firmly seat themselves and the member 16 inplace. Alternatively, of course, the teeth might be made of the softermaterial; in either case a firm seating is secured. For securing thiseffect, the'teeth are shown as provided with sharp edges taperingdownwardly, and when the member [6 is drawn against the shank by thescrew 20, the two rows of teeth 44 will wedge into the opening 36 andthe parts will be firmly interlocked.

When the body portion ID, and the shank l2, the interlocking member l6and the washer M are in assembled relation, it will be observed thatthey mutually firmly support each other in the proper relation.Permanence in such assembled relation is secured by inserting the screw28 through the opening 46 of the flange 41 at the top of the threadedbore 48 of the shank, and into the threaded opening 58 in the member It.

The lock. washer 22 may be placed under the head of the screw 2!! andwill then perform its customary function of resisting movement of thescrew, such as would loosen it.

The ease with which the assembly of the parts may be eifected will beapparent. The washer M is first placed in the shank l2, the body portionI8 is seated in the washer, and the member i5 is properly positioned byinserting it through the open end of the body portion Ill and seating itin place in the opening 30 and on the shank 12. The parts are readilyheld in place while the screw 20 and lock washer 28 are applied to drawthe parts together.

Adjacent the exterior portion of the knob I8 I form an annular flange 58into which the rim of the washer I l may be seated.

The washer is preferably dished to add resiliency and where it is seatedover the lugs 36 abuts the shoulder 31 formed on the shank l2 andextending to either side of the upstanding lugs 36. Interposing thewasher 14 between the knob 10 and the shoulder 31 provides anexceedingly desirable construction especially where the washer I l isdished in that by this construction the bottom 28 of the knob where thisis made of rather fragile plastic material is resiliently engagedbetween the interlocking member I6 and the shoulder 31. This resiliencyis in addition to that which may be offered by the spring washer 22.Additionally also, by separately forming the shank l2 and the washer l4great economy is effected by reason of the fact that the stock ofmaterial which is employed for making the shank I2 is of minimumdimension.

Additionally, also, apart from the resilient connection obtained ininterposing the washer l4 between the knob 10 and the shoulder 31 of theshank 12 quick interchange of parts may be effected so that a definitecolor combination may be obtained as between the ornamental finish whichmay be given to the washer I 4 and the doorknob [0. Thus, as willhereinafter appear, if the chromium plating, nickel plating, gun metalor colored enamel finish is intended to be contrasted with the colortone of the doorknob l8 whether it be made of metal or plastic, theinterposing of the washer l4 and its manner of mounting makes possible aquick and ready interchange of this part with the desired color tone orwith any other predetermined color tone depending upon the colorcombination to be effected by the assembly.

To complete the doorknob and to give it its final ornamental touch thetop piece I8 is added to the assembly just described. It is shown asprovided with prongs 52 adapted to enter the grooves 24 of the bodyportion Ill. The prongs 52 are made sufiiciently resilient and they havetransverse grooves 54 in the outer surfaces of their end portions, sothat when they are inserted into the grooves 24 of the body portion [0they will snap into place, with the rib-s 26 of the body portion seatedin the grooves 54 of prongs, as shown in Fig. 2.

Disassembly of the complete knob for the purpose of interchanging partsor for other purposes is readily efiected by first removing the screw28, which will enable separation of the shank l2 (and the washer l4 ifdesired) and then pushing the member l6 inwardly and against the toppiece thereby forcing it out of its seat in the body portion.

For the sake of completeness attention may be called to the threadedbore 48, adapted to fit on a threaded spindle and the threaded opening56 adapted to receive a screw to lock the knob to the spindle, thesebeing conventional features.

Attention will now be directed to the simplicity and economy of designenabling my improved doorknob to be produced at low cost. The use ofmetals or of synthetic plastics of different color-tones or ornamentalfinish for the body portion Ill has already been mentioned, The memberI6 is conveniently and cheaply made of metal by the die casting process.The spindle or shank I2 is a turning that is relatively low in costbecause of the small diameter of the stock that may be used. The toppiece l8 and the washer l4 are sheet metal stampings that may be cheaplyand easily produced and given various predetermined finishes ofornamental character for effecting various color combinations with theknob portions.

It will therefore be obvious that by the ready interchangeability of theparts of my doorknob and their low cost, great variety in colorcombinations and finish may be obtained by a dealer or a manufacturerfrom a stock of parts that are small in quantity and low in cost.

Having thus described and illustrated my invention, what I desire tosecure by Letters Patent is:

1. A doorknob comprising a hollow body portion open at the top andhaving a non-circular opening in its bottom and a shallow recess on itsbottom surface, a top piece adapted to close the opening in the top ofthe body portion, said piece and said body portion .being provided withcomplementary means for yieldably interlocking them, a washer seating insaid recess of the body portion, a shank having spaced projectionsthereon extending through the opening in the washer, a member havingportions adapted to seat snugly within the opening in the bottom of saidbody portion when pressed thereinto, said member having recesses thereinadapted to receive said projections on the shank, and said member havinga projection thereon adapted to extend and to fit into the space betweensaid projections on the shank, and means for drawing said member towardthe shank and thereby to snugly interlock said member, said bodyportion, said washer and said shank.

2. In a doorknob assembly constituted of readily interchangeable parts,a shank arranged to receive a spindle, a resilient washer seating onsaid shank, a hollow body portion seating on said washer, and means tointerlock said body portion and said shank portion against separationand relative rotation independent of said spindle, said means being ofsuch character as to permit its ready removal when desired, and readilyremovable closure means for said hollow body portion, seating thereinindependently of said interlocking means.

3. A doorknob construction comprising a relatively heavy metallic shank,a relatively heavy hollow body portion, a dished, resilient sheet metalwasher interposed between said body portion and said shank, a relativelyheavy member for interlocking said shank and said body portion againstseparation and relative rotation, and a thin sheet metal closure forsaid hollow body portion, said closure seating on and interlocking withthe said body portion independently of said interlocking means 4. Adoorknob construction comprising a relatively heavy metallic shankarranged to receive a threaded spindle, a relatively heavy hollow bodyportion made of a molded synthetic plastic material, a dished, resilientsheet metal washer interposed between said body portion and said shank,a relatively heavy member for interlocking said shank and said bodyportion against separation and relative rotation independent of saidspindle, and a thin sheet metal closure for said hollow body portion,said closure seating on and interlocking with the said body portionindependently of said interlocking means.

5. A doorknob comprising a shank, a washer seating on said shank, a bodyportion adapted to seat on said washer, a member adapted to seat on saidshank and having portions thereon interfitting with said body portion,said member serving to interlock said shank and said body portion andprevent separation and relative rotation thereof, and means for holdingsaid member in its interlocking position.

6. A shank for a doorknob, said shank being of tubular conformation andprovided at one end thereof with spaced projections having their outerwalls contoured so as to lie in a single cylindrical segment, an'annularseat surrounding said projections, and a restricted opening between saidprojections, said opening communicating with the bore of the shank.

7. A shank for a doorknob, said shank being of turned tubularconformation and having a threaded bore, and said shank being providedat one end thereof with spaced projections having their outer wallscontoured so as to lie in a single cylindrical segment, an annular seatsurrounding said projections, and a restricted opening between saidprojections, said opening com,- municating with the bore of the shank.

8. In a doorknob, in combination, a shank of substantially tubularconformation and having a threaded bore provided at one end with spacedprojections defining the inner cylindrical wall of an annular seat, andan opening communicating with said bore between said projections, and awasher seating on said annular seat and surrounding said projections,said washer being adapted to be seated in the body portion of a doorknobto engage peripheral portions of said washer. p t

9. In a doorknob, a bowl-shaped body portion having walls following thegeneral exterior contour of said body having a non-circular opening inits bottom, closure means for the open top of said body portion, andcomplementary means on said closure and said body portion for removablyinterlocking them, said complementary means comprising resilient memberscarried by said closure means and adapted to extend into grooves in theinner walls of said body portion and a shouldered portion on theinterior faces of said walled portion to limit said closure means toinward positioning to arrange said closure and knob body to formpredetermined contoured portions. v

10. In a doorknob, a hollow body portion the walls of which followgenerally the exterior contour of said body and provided with grooves inits inner walls having transverse ribs therein and adapted to receivethe complementarily contoured portions of a top piece forming a coverfor said body portion, said ribs forming an abutment for said top pieceto limit the positioning of said cover to the contoured portion.

11. In a doorknob assembly comprising a body portion, a shank and awasher interposed between said body portion and said shank, a member forinterlocking said parts comprising a portion adapted to interlock withthe body portion of the doorknob and a portion adapted to interlock withthe shank, and means adapted to engage said member whereby the saidmember may be drawn toward the shank so as to hold said body portion,said washer and said shank in interlocking relation.

12. In a doorknob assembly comprising a body portion, a shank and awasher interposed between said body portion and said shank, a member forinterlocking said parts comprising a portion adapted to interlock withthe body portion of the doorknob and a portion adapted to interlock withthe shank, and means adapted to engage said member whereby the saidmember may be drawn toward the shank so as to hold said body portion,said Washer and said shank in interlocking relation, and said memberbeing provided with teeth having inclined sides adapted to be forcedinto the material of the body portion when said member is drawn towardthe shank.

13. In a doorknob assembly comprising a body portion of relatively softmaterial and a shank for receiving a spindle, a member independent pressagainst said body portion.

14. A doorknob assembly comprising a body portion of relatively softmaterial and a shank for receiving a spindle, a member for interlockingsaid shank and said body portion to each other and located within theconfines of the body of said knob, said member being of relatively hardmaterial and being provided with wedge shaped teeth adapted to bite intothe body portion when pressed thereagainst and thereby to eliminate playbetween them, and means for causing said member to press against saidbody portion.

15. In a doorknob assembly comprising a body portion and a shank adaptedto receive a spindle .in independently adjustable relationship, a memberfor interlocking said shank and said body portion, means acting betweensaid shank and said member for drawing said member toward the shank, andcausing portions of said member to engage and to press against said bodyportion, and said engaging portions of said member and of said bodyportion being respectively of materials one of which is relatively softand the other of which is relatively hard, whereby when said memberengages and is pressed against said body portion the softer materialwill be deformed by the harder material which will bite thereinto andthe parts will be firmly seated together.

16. In a hollowdoorknob adapted to be attached to a shank, independentlyof a spindle connection, a knob body of bowl shape, open at the top,vertic'al grooves in the inner sides of the walls of said knob body,ribs running transversely across said grooves, and a closure for theopen top of said knob body comprising a. disc-shaped portion havingresilient prongs depending therefrom, said prongs being adapted to entersaid grooves in the knob body, and said prongs having transverse groovestherein adapted to receive said ribs in the grooves of said knob bodywhereby relative rotation of the cover and thebody is prevented andremoval of the cover from the body is resisted.

17. In a doorknob, a knob member having a non-circular openingtherethrough, a knob shank having a relatively long body portionabutting at one end one face of the knob member, a relatively shortextension having an opening on said abutting end entering the knobmember opening, said abutting portion having a spindle receiving borecommunicating with the opening of said extension, a. securing memberoperable independently of the spindle for said shank having an enlargedhead disposed in said extension and having a portion projecting intosaid opening, and a retaining member having means at the opposite faceof a portion of the knob member non-rotatably engaging said opening andto which said securing member is connected.

18. In a doorknob, a knob member having an opening therethrough,portions adjacent thereof being formed to provide non-rotativeengagement, aknob shank adapted to receive a spindle having a relativelylong body portion abutting at oneend one face of the knob member, arelatively short extension having an opening on said abutting end andentering said knob member opening, said abutting portion having aspindle receiving bore communicating with the opening of said extension,securing means adjacent said extension aligned with the opening of saidknob member, and a retaining member operative independently of saidspindle for said shank havingv means at the opposite face of a portionof the knob disposed through the opening of said knob member andengaging said securing means, non-rotatably holding said knob member andknob shank.

MORRIS FALK.

